U.S. patent number 7,635,221 [Application Number 12/325,663] was granted by the patent office on 2009-12-22 for mechanically flexible x-ray imaging system.
This patent grant is currently assigned to Siemens Medical Solutions USA, Inc.. Invention is credited to Martin Spahn.
United States Patent |
7,635,221 |
Spahn |
December 22, 2009 |
Mechanically flexible X-ray imaging system
Abstract
An X-ray imaging system includes a joint enabling rotation of an
X-ray device rotatable arm unrestricted by cabling. An X-ray
imaging system usable in medical interventional procedures includes
a rotatable arm. A rotatable arm includes an X-ray radiation
emitting device located towards one end of the rotatable arm and an
X-ray detector device located towards the opposite end of the
rotatable arm. The detector device acquires X-ray radiation emitted
by the emitting device that has passed through a patient. A base
unit supports the rotatable arm and includes a joint enabling
rotation of the rotatable arm unrestricted by cabling, about a
patient on a support surface. The joint includes, (a) mating
electrical contact surfaces providing electrical power to the
rotatable arm from the base unit during rotation of the rotatable
arm unrestricted by cabling and (b) a signal interface for
providing electrical signals received from the rotatable arm to the
base unit during rotation of the rotatable arm unrestricted by
cabling. An X-ray imaging system controller controls application of
electrical power to the rotatable arm via the base unit.
Inventors: |
Spahn; Martin (Erlangen,
DE) |
Assignee: |
Siemens Medical Solutions USA,
Inc. (Malvern, PA)
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Family
ID: |
40850620 |
Appl.
No.: |
12/325,663 |
Filed: |
December 1, 2008 |
Prior Publication Data
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Document
Identifier |
Publication Date |
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US 20090180595 A1 |
Jul 16, 2009 |
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Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
Issue Date |
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61020485 |
Jan 11, 2008 |
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Current U.S.
Class: |
378/194;
378/197 |
Current CPC
Class: |
A61B
6/4233 (20130101); A61B 6/4441 (20130101); A61B
6/563 (20130101); A61B 6/4488 (20130101); A61B
6/56 (20130101); A61B 6/4464 (20130101) |
Current International
Class: |
H05G
1/06 (20060101) |
Field of
Search: |
;378/193-198,4-20 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Song; Hoon
Claims
What is claimed is:
1. An X-ray imaging system usable in medical interventional
procedures, comprising: a rotatable arm including an X-ray
radiation emitting device located towards one end of said rotatable
arm and an X-ray detector device located towards the opposite end
of said rotatable arm, said detector device acquiring X-ray
radiation emitted by the emitting device and having passed through
a patient; a base unit supporting said rotatable arm and including
a joint or pivot enabling rotation of said rotatable arm
unrestricted by cabling, about a patient on a support surface, said
joint or pivot including, (a) mating electrical contact surfaces
providing electrical power to said rotatable arm from said base
unit during rotation of said rotatable arm unrestricted by cabling
and (b) a signal interface for providing electrical signals
received from said rotatable arm to at least one of, said base unit
and a processing device, during rotation of said rotatable arm
unrestricted by cabling; and an X-ray imaging system controller for
controlling application of electrical power to said rotatable arm
via said base unit.
2. A system according to claim 1, wherein said mating electrical
contact surfaces provide, (a) first voltage electrical power to
said rotatable arm and (b) different second voltage electrical
power to said rotatable arm, said second voltage electrical power
being high voltage relative to said first voltage and for use in
providing X-ray emission.
3. A system according to claim 2, wherein said mating electrical
contact surfaces are spaced and insulated to maintain electrical
isolation between the first and second different voltages.
4. A system according to claim 1, wherein said mating electrical
contact surfaces comprise concentric electrical contact rings.
5. A system according to claim 1, wherein said signal interface for
providing electrical signals received from said rotatable arm
comprises mating electrical contact surfaces.
6. A system according to claim 1, wherein said signal interface for
providing electrical signals received from said rotatable arm
comprises a wireless electrical signal interface.
7. A system according to claim 1, wherein said signal interface for
providing electrical signals received from said rotatable arm
comprises a wireless optical signal interface.
8. A system according to claim 1, wherein said signal interface for
providing electrical signals received from said rotatable arm
comprises a wireless capacitive coupling signal interface.
9. A system according to claim 1, wherein said signal interface
bidirectionally exchanges electrical signals between said rotatable
arm and said base unit.
10. A system according to claim 1, wherein said rotatable arm
includes a high voltage power supply unit for generating relatively
high voltage electrical power using relatively low voltage
electrical input power, said relatively high voltage electrical
power being for use in providing X-ray emission and said relatively
low voltage electrical input power being provided via said mating
electrical contact surfaces.
11. A system according to claim 1, wherein said rotatable arm
includes a cooling unit for providing device cooling using
relatively low voltage electrical input power, said relatively low
voltage electrical input power being provided via said mating
electrical contact surfaces.
12. A system according to claim 1, wherein said joint or pivot
enables 360 degree rotation of said rotatable arm in at least one
plane.
13. A system according to claim 1, wherein said rotatable arm
comprises a rotatable C-arm.
14. An X-ray imaging system usable in medical interventional
procedures, comprising: a rotatable arm including an X-ray
radiation emitting device located towards one end of said rotatable
arm and an X-ray detector device located towards the opposite end
of said rotatable arm, said detector device acquiring X-ray
radiation emitted by the emitting device and having passed through
a patient; a base unit supporting said rotatable arm and including
a joint or pivot enabling rotation of said rotatable arm
unrestricted by cabling, about a patient on a support surface, said
joint including, (a) mating electrical contact surfaces providing
electrical power to said rotatable arm from said base unit during
rotation of said rotatable arm unrestricted by cabling and (b) a
wireless electrical signal interface for providing electrical
signals received from said rotatable arm to at least one of, said
base unit and a processing device, during rotation of said
rotatable arm unrestricted by cabling; and an X-ray imaging system
controller for controlling application of electrical power to said
rotatable arm via said base unit.
15. A system according to claim 14, wherein said mating electrical
contact surfaces provide, (a) first voltage electrical power to
said rotatable arm and (b) different second voltage electrical
power to said rotatable arm, said second voltage electrical power
being high voltage relative to said first voltage and for use in
providing X-ray emission.
16. A system according to claim 15, wherein said first voltage
electrical power powers a collimator and SID
(source-imager-distance) drive unit including mechanical drives for
SID, detector and collimator rotation.
17. A system according to claim 15, wherein said mating electrical
contact surfaces are spaced and insulated to maintain electrical
isolation between the first and second different voltages.
18. A system according to claim 14, wherein said wireless
electrical signal interface comprises at least one of, (a) a Wi-Fi
link, (b) a WIMAX link and (c) another broadband local
point-to-point network link.
Description
This is a non-provisional application of provisional application
Ser. No. 61/020,485 filed Jan. 11, 2008, by M. Spahn.
FIELD OF THE INVENTION
This invention concerns an X-ray imaging system usable in medical
interventional procedures, comprising a rotatable arm, supporting
an X-ray radiation emitting device and being movable about a
patient on a support surface unrestricted by cabling.
BACKGROUND OF THE INVENTION
Known interventional X-ray systems use a movable arm such as a
C-arm, to support an X-ray emitter and a detector. A C-arm may be
floor-mounted or ceiling mounted. A C-arm may also be mounted on a
robotic stand to provide flexible, automated arm manipulation. An
X-ray detector and emitter, as well as motor drives require
electrical power, electronic data and control signals to be
provided via cables and may also require coolant connections if a
detector requires cooling, for example. Electrical cables and wires
as well as cooling tubes are usually incorporated within a thick
support cable housing or tube. Due to the support cable, the
degrees of freedom of the C-arm or robotic stand are limited. In
X-ray image acquisition of a three dimensional (3D) anatomical
volume, C-arm movement may be limited to between 180 and 360
degrees of C-arm rotation, for example. Continuous rotation,
involved in spiral-CT (Computerized Tomography) is not possible for
interventional systems constrained by a support cable. Also, X-ray
mask and content (non-mask) imaging acquisitions require a C-arm to
be moved back and forth, which requires more time than an
alternative continuous rotation (with mask and content image
acquisitions occurring successively) and this is more prone to
introduction of motion artifacts due to patient movement. A system
according to invention principles addresses these deficiencies and
related problems.
SUMMARY OF THE INVENTION
Known interventional X-ray imaging systems including C-arm and
robotic systems, use an external cable to provide high voltage to
an X-ray emission tube as well as electrical and possibly cooling
connections to an X-ray detector. The cable limits the degrees of
freedom of the C-arm. An X-ray imaging system includes a joint
enabling rotation of a rotatable arm unrestricted by cabling using
contact rings, wireless data transmission and detectors which do
not require external cooling, enabling spiral CT type movement of a
C-arm possible, for example. An X-ray imaging system usable in
medical interventional procedures includes a rotatable arm. A
rotatable arm includes an X-ray radiation emitting device located
towards one end of the rotatable arm and an X-ray detector device
located towards the opposite end of the rotatable arm. The detector
device acquires X-ray radiation emitted by the emitting device that
has passed through a patient. A base unit supports the rotatable
arm and includes a joint enabling rotation of the rotatable arm
unrestricted by cabling, about a patient on a support surface. The
joint includes, (a) mating electrical contact surfaces providing
electrical power to the rotatable arm from the base unit during
rotation of the rotatable arm unrestricted by cabling and (b) a
signal interface for providing electrical signals received from the
rotatable arm to the base unit during rotation of the rotatable arm
unrestricted by cabling. An X-ray imaging system controller
controls application of electrical power to the rotatable arm via
the base unit.
BRIEF DESCRIPTION OF THE DRAWING
FIGS. 1 and 2 show known X-ray imaging systems involving support
cabling.
FIG. 3 shows an X-ray imaging system comprising a robotic base unit
supporting a rotatable arm via a joint enabling rotation of the
rotatable arm unrestricted by cabling, according to invention
principles.
FIG. 4 shows an X-ray imaging system comprising a robotic base unit
supporting a rotatable arm with integrated cooling unit and using a
joint enabling rotation of the rotatable arm unrestricted by
cabling, according to invention principles.
FIG. 5 shows an electrical contact arrangement employed by a joint
enabling rotation of an X-ray imaging system rotatable arm
unrestricted by cabling, according to invention principles.
FIGS. 6A and 6B show a knee-type joint with contact segments and
carbon or graphite brushes for power transmission enabling rotation
of an X-ray imaging system rotatable arm unrestricted by cabling,
according to invention principles.
FIG. 7 shows a wireless X-ray detector photodiode matrix with
high-speed W-Fi (or other broadband) connection for real-time
signal and image data transmission, according to invention
principles.
DETAILED DESCRIPTION OF THE INVENTION
An X-ray imaging system comprises a robotic base unit supporting a
rotatable arm via a joint enabling rotation of the arm unrestricted
by cabling. The system overcomes mechanical restrictions imposed on
movement of a movable X-ray imaging system arm by external cabling
and enables X-ray imaging to be performed on larger anatomical
volumes in a continuous motion or rotation. The system eliminates
support cabling using a joint including, mating electrical contact
surfaces providing electrical power and signals to a rotatable arm
from a base unit during rotation of the arm unrestricted by
cabling. In one embodiment, a joint conveys high voltage (e.g., for
X-ray emission tube) and low voltage (e.g., for an X-ray detector,
motor drives) via contact rings. Alternatively, high voltage
generation is integrated into a C-arm, so that only relatively low
voltage needs to be supported via contact rings. The contact rings
(or segments) may comprise metal (for example Copper), isolated
from surroundings on one side of the joint (also comprising a
pivot) and brushes (carbon or graphite brushes) on the other
side.
In one embodiment, low voltages (low relative to the high voltage
used for X-ray emission) are conveyed in the joint via contact
rings and used to power an X-ray detector, a collimator, a dose
meter, other subsystems requiring power which are mounted on the
arm and various motors for moving the robotic arm, rotation of the
collimator and detector on the arm and SID (source-imager-distance)
movement, for example. In an alternative embodiment, the relatively
low voltages or signals are conveyed via contact-less capacitive
coupling in the joint. Further, X-ray image detector image data and
control signals may be conveyed in a joint by different
arrangements including, contact rings, a wireless interface (such
as a Wi-Fi link, WIMAX or other broadband local point-to-point
network), contact-less optical interface (e.g., an opto-isolator)
and contact-less capacitive coupling. In order to eliminate cooling
related cabling, the system employs an X-ray detector that does not
need cooling or if it does require cooling, the detector uses
air-cooling (such as a fan) or otherwise the cooling unit (water or
other fluid) is directly integrated into the arm. Also the arm may
have integrated cooling fins to divert heat into the surrounding
air. The different methods used to eliminate external cabling may
be combined in a variety of different combinations.
A processor as used herein is a device for executing stored
machine-readable instructions for performing tasks and may comprise
any one or combination of, hardware and firmware. A processor may
also comprise memory storing machine-readable instructions
executable for performing tasks. A processor acts upon information
by manipulating, analyzing, modifying, converting or transmitting
information for use by an executable procedure or an information
device, and/or by routing the information to an output device. A
processor may use or comprise the capabilities of a controller or
microprocessor, for example. A processor may be electrically
coupled with any other processor enabling interaction and/or
communication there-between. A processor comprising executable
instructions may be electrically coupled by being within stored
executable instruction enabling interaction and/or communication
with executable instructions comprising another processor. A user
interface processor or generator is a known element comprising
electronic circuitry or software or a combination of both for
generating display images or portions thereof. A user interface
comprises one or more display images enabling user interaction with
a processor or other device.
An executable application comprises code or machine readable
instructions for conditioning the processor to implement
predetermined functions, such as those of an operating system, a
context data acquisition system or other information processing
system, for example, in response to user command or input. An
executable procedure is a segment of code or machine readable
instruction, sub-routine, or other distinct section of code or
portion of an executable application for performing one or more
particular processes. These processes may include receiving input
data and/or parameters, performing operations on received input
data and/or performing functions in response to received input
parameters, and providing resulting output data and/or parameters.
A user interface (UI), as used herein, comprises one or more
display images, generated by a user interface processor and
enabling user interaction with a processor or other device and
associated data acquisition and processing functions.
The UI also includes an executable procedure or executable
application. The executable procedure or executable application
conditions the user interface processor to generate signals
representing the UI display images. These signals are supplied to a
display device which displays the image for viewing by the user.
The executable procedure or executable application further receives
signals from user input devices, such as a keyboard, mouse, light
pen, touch screen or any other means allowing a user to provide
data to a processor. The processor, under control of an executable
procedure or executable application, manipulates the UI display
images in response to signals received from the input devices. In
this way, the user interacts with the display image using the input
devices, enabling user interaction with the processor or other
device. The functions and process steps herein may be performed
automatically or wholly or partially in response to user command.
An activity (including a step) performed automatically is performed
in response to executable instruction or device operation without
user direct initiation of the activity. An object or data object
comprises a grouping of data, executable instructions or a
combination of both or an executable procedure.
FIGS. 1 and 2 show known X-ray imaging systems involving support
cabling. FIG. 1 shows robotic stand 10 and support cable 12
powering X-ray detector 14 and X-ray tube and collimator 17 mounted
on C-arm 15 as well as mechanical drives. Cable 12 also conveys
data and control signals and possibly includes a cooling tube
conveying coolant for detector 14. The system performs
interventional angiography and two dimensional and three
dimensional (2D and 3D) image data acquisition for a patient on
table 18.
FIG. 2 shows a ceiling mount 20 C-arm interventional X-ray imaging
system with support cable 22 powering X-ray detector and SID
(source-imager-distance) drive 24 and X-ray emission tube and
collimator 27 mounted on C-arm 25 as well as mechanical drives for
SID, detector and collimator rotation. Generator 34 provides the
electrical power conveyed via cable 22. Cable 22 also conveys data
and control signals and may include a cooling tube conveying
coolant for detector 14. The system performs interventional
angiography and two dimensional and three dimensional (2D and 3D)
image data acquisition for a patient on table 28. User interface 26
presents medical images and the system is controlled by system
imaging control unit 32.
FIG. 3 shows X-ray imaging system 100 usable in medical
interventional procedures, according to invention principles,
comprising a robotic base unit 40 supporting a rotatable arm (e.g.,
C-arm) 45 via joints and pivots 70 enabling rotation of the
rotatable arm about patient table 48 unrestricted by cabling. A
robotic base 40 advantageously drives C-arm 45 through multiple
joints and pivots 70 (four joints are shown in FIG. 3) in three
axes of motion including rotation and supporting a full range of
motion about a patient positioned on patient table 48. The joints
or pivots 70 enable 360 degree rotation of rotatable C-arm 45 in at
least one plane. System 100 is an interventional X-ray imaging
system with electrical low and high voltage power being integrally
conveyed within the stand 40 and C-arm 45 through contact rings in
joints and pivots 70, for example. Image data as well as data and
control signals are communicated via wireless communication between
system image processing and control unit 42 and wireless X-ray
detector image data and control interface 44 on C-arm 45. The C-arm
45 devices also include X-ray emission tube, collimator and SID
(source-imager-distance) drive unit 47 including mechanical drives
for SID, detector and collimator rotation. The wireless X-ray
detector in unit 44 does not require cooling in this
embodiment.
FIG. 7 shows wireless X-ray detector photodiode matrix 709 in unit
703 used in interface 44 (FIG. 3) communicating via high-speed W-Fi
(or other broadband) connection provided by electronics 705 and 711
for real-time signal and image data transmission to unit 42.
Wireless X-ray detector unit 703 supports high frame-rate X-ray
image data acquisition and transmission applications (for example
up to 60-100 frames per second). Detector photodiode matrix 709
comprises an integrating detector based on a-Si (amorphous silicon)
active matrix and a CsI (cesium iodide) scintillator 707.
Rotatable C-arm 45 of FIG. 3 includes X-ray radiation emitting
device 47 located towards one end of rotatable arm C-arm 45 and
X-ray detector device 44 located towards the opposite end of
rotatable C-arm 45. Detector device 44 acquires X-ray radiation
emitted by emitting device 47 having passed through a patient on
table 48. Base unit 40 supports rotatable C-arm 45 and includes
joints and pivots 70 enabling rotation of rotatable C-arm 45
unrestricted by cabling, about a patient on a support surface
(table) 48. Joints and pivots 70 include mating electrical contact
surfaces providing electrical power to rotatable C-arm 45 from base
unit 40 during rotation of rotatable C-arm 45 unrestricted by
cabling. The mating electrical contact surfaces provide, (a) first
voltage electrical power to the rotatable arm and (b) different
second voltage electrical power to the rotatable arm. Further, the
mating electrical contact surfaces are spaced and insulated to
maintain electrical isolation between the first and second
different voltages. The first voltage electrical power powers a
collimator and SID (source-imager-distance) drive unit 47 including
mechanical drives for SID, detector and collimator rotation. The
second voltage electrical power is a high voltage relative to the
first voltage and is for use in providing X-ray emission, for
example. A wireless electrical (or optical) signal interface in
unit 44 provides electrical signals received from rotatable C-arm
45 to unit 42 (which may be part of base unit 40 or a processing
device) during rotation of rotatable C-arm 45 unrestricted by
cabling. X-ray imaging system controller 42 controls application of
electrical power to rotatable C-arm 45 via base unit 40. In one
embodiment, the mating electrical contact surfaces comprise
concentric electrical contact rings.
Other embodiments involve different methods of conveying relatively
high and low power, relatively high and low voltage, image data,
control signals and of providing cooling. The wireless X-ray image
detector interface in unit 44 may comprise a Wi-Fi link, WIMAX or
other broadband local point-to-point network link. If the X-ray
image detector in unit 44 requires cooling, C-arm 45 (and its
entire mass) may be used to remove the heat. In one embodiment,
rotatable arm C-arm 45 includes a high voltage power supply unit
for generating relatively high voltage electrical power using
relatively low voltage electrical input power. The relatively high
voltage electrical power being for use in providing X-ray emission
and the relatively low voltage electrical input power being
provided via the mating electrical contact surfaces. In another
embodiment, unit 44 comprises a non-cooled detector with an optical
data and control signal interface for conveying signals through
joints and pivots 70 in robotic stand 40. The X-ray image detector
in unit 44 adaptively operates at different frame rates, including
1, 2, and 4 image frames per second (fps) for Digital Subtraction
Angiography (DSA) applications or road mapping, 15 fps for
fluoroscopy or up to 60-100 fps (or even higher) for three
dimensional (3D) anatomical volume image data acquisitions. The
X-ray image detector in unit 44 may comprise an integrating
detector based on a-Si (amorphous silicon) active matrix and a CsI
(cesium iodide) scintillator. Alternately, the detector may be a
counting detector and use direct-conversion X-ray materials.
FIG. 4 shows X-ray imaging system 200 comprising robotic base unit
240 supporting rotatable C-arm 245 with integrated cooling unit 251
and using joints and pivots 270 enabling rotation of rotatable
C-arm 245 unrestricted by cabling. Imaging system 200 comprises a
diagnostic and interventional X-ray imaging system comprising
robotic stand 240 without external cables and with high voltage
power and low voltage power being integrally conveyed within stand
240 and C-arm 245 through contact rings in joints and pivots 270.
Image and control signals including unidirectional and
bidirectional data and control signals are transferred via mating
electrical contact surfaces or wireless optical or capacitive
coupling interfaces in joints and pivots 270, between C-arm 245 and
base unit 240 or another device. The X-ray image detector 244 is
cooled by cooling unit 251 integrated into C-arm 245. Cooling unit
251 provides device cooling using relatively low voltage electrical
input power and the relatively low voltage electrical input power
is provided via the mating electrical contact surfaces. Rotatable
C-arm 245 includes X-ray radiation emitting device 247 located
towards one end of rotatable arm C-arm 245 and X-ray detector
device 244 located towards the opposite end of rotatable C-arm 245.
Detector device 244 acquires X-ray radiation emitted by emitting
device 247 having passed through a patient on table 248. X-ray
imaging system controller 242 controls application of electrical
power to rotatable C-arm 245 via base unit 240.
FIG. 5 shows an electrical contact arrangement employed by a joint
enabling rotation of an X-ray imaging system rotatable arm
unrestricted by cabling. The joint allows continuous rotation
around central axis 511 within joint boundary 513. Metal contact
rings 503 and 505 provide high and low voltage power transmission
through a joint, respectively. Metal contact rings 507 provide
image data, control data and signal data transmission, through a
joint, respectively. The contact rings are isolated from each other
by insulated spacing 509.
FIGS. 6A and 6B show a knee-type joint with contact segments and
carbon or graphite brushes for power transmission enabling rotation
of an X-ray imaging system rotatable arm unrestricted by cabling.
FIG. 6A shows a two dimensional view showing the joint without
cabling. FIG. 6B shows a three dimensional view showing both parts
of the joint 610 and 615 in a separated view indicating high
voltage contact segments 603 and low voltage contact segments 609.
Contact segments 603 and 609 electrically mate with carbon brushes
618. The high and low voltage segments are separated by isolation
distance 629. Electrical power is conveyed within robotic arm via
cabling 607 and 613.
The systems of FIGS. 1-7 are not exclusive. Other systems and
processes may be derived in accordance with the principles of the
invention to accomplish the same objectives. Although this
invention has been described with reference to particular
embodiments, it is to be understood that the embodiments and
variations shown and described herein are for illustration purposes
only. Modifications to the current design may be implemented by
those skilled in the art, without departing from the scope of the
invention. Further, the processes and applications may, in
alternative embodiments, be located on one or more (e.g.,
distributed) processing devices. Any of the functions and steps
provided in FIGS. 1-7 may be implemented in hard, software or a
combination of both.
* * * * *